There is a steering apparatus enabling positions in up-and-down directions or back-and-forth directions of the steering wheel to be adjusted corresponding to the physical constitution and the driving position of the driver. This type of steering apparatus is configured so that after completing an adjustment of a tilt position or a telescopic position, a driver operates an operation lever, consequently a fastening rod fastens a column together with side plates of a vehicle body fitting bracket, and the column is thus fixed so as to be disabled from making a tilt or telescopic movement. Further, the vehicle body fitting bracket is constructed to, when a predetermined impact load is applied thereto, remove from a vehicle body, to then move towards a front side of the vehicle body and to relax the impact load applied to the driver.
In the steering apparatus such as this, if the force of fixing the column is small, upon the secondary collision at which the driver collides with a steering wheel, before the vehicle body fitting bracket gets removed from the vehicle body, the impact load is apt to cause the column to be moved upward, or an outer column 11 to be moved forward in some cases. This being the case, caused by the secondary collision, there occurs a dispersion in load in a collapse direction due to the secondary collision such as a reduction in load applied to the steering wheel 12 in the collapse direction, resulting in difficulty in designing an impact absorbing mechanism.
Accordingly, an apparatus configured to fix the column to the vehicle body fitting bracket is requested to have rigidity when fixed and stabilize the fixing force. Moreover, the apparatus is also requested to facilitate an unclamping operation by taking convenience of the driver into consideration. Such being the case, as disclosed in Patent document 1, a structure is adopted, in which the side plates of the vehicle body fitting bracket and the column are fastened via friction plates in some instances.
The clamp apparatus using such friction plates is, as disclosed in Patent document 1, that tilt friction plates each formed long in a tilt adjustment direction is fixed to the vehicle body fitting bracket, telescopic friction plates each formed long in a telescopic adjustment direction is fixed to the column, and washers are interposed between the respective friction plates to increase the number of friction faces, thereby augmenting the friction force. According to this apparatus, the washers interposed between the respective friction plates lead to increase in dimension of the steering apparatus in the vehicle widthwise direction, in number of components, and in weight of the steering apparatus.